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PPIMV QA - 250K, 100K with resistors...?

Posted: Wed Feb 15, 2012 6:39 pm
by bmwfreq
I currently have the Lar/Mar PPIMV mod kit installed in my JCM 800, and I'm using EL34 power tubes. I want to convert them to 6550's, but I want to use the dual 250K pots that came with the kit. My question is, can I install 170K ohm resistors across the pots (see diag.) to get me in the neighborhood of an 82K (final value) output grid resistor, or, will I need to replace the pots altogether??

Re: PPIMV QA - 250K, 100K with resistors...?

Posted: Tue Mar 05, 2013 9:34 pm
by Capel
Don't know how relevant this is for your 800 (I'm assuming it's 100W), but here's the schematic BRMSlash worked out for the Ceriatone AFD#35 which has PPIMV with 250K pots into 6550's: http://flic.kr/p/dWsfkZ" onclick="window.open(this.href);return false;
Hope that helps